This study investigated the effectiveness of a 20-week Simulated Developmental Horse-Riding Program (SDHRP) by using an innovative exercise equipment (Joba[R]) on the motor proficiency and sensory integrative functions in 60 children with autism (age: 6 years, 5 months to 8 years, 9 months). In the first phase of 20 weeks, 30 children received the SDHRP in addition to their regular occupational therapy while another 30 children received regular occupational therapy only. The arrangement was reversed in the second phase of another 20 weeks. Children with autism in this study showed improved motor proficiency and sensory integrative functions after 20-week SDHRP (p less than 0.01). In addition, the therapeutic effect appeared to be sustained for at least 24 weeks (6 months). (Contains 5 tables.)